KN-95 vs N-95 4

[TugboatEng]

Now that the winds are starting to calm down, maybe it's time that review the engineering information. It's odd that our USA CDC NEVER recommended the use of KN-95 masks. They never existed before 2020 and why would a Chinese standard use USA characters? The CDC edicts always stated N-95 and it was only our media that tacked on the N-95 "OR" KN-95 terminology. Talk about spreading misinformation. If N-95 is truely effective, how much blood is on the hands of our media for pushing the fake KN-95 standard? Also, the waste and pollution...

I'm really surprised that no engineers that understand anything about filtration came forward on this? A piece of Saran Wrap filters better than a N-95. How is the KN-95 standard relevant?

 

[RedSnake]

It is not the standards that is the problem here, it is the same problem that always occurs when demand is higher than supply, that people and companies starts cutting corners.
And I would say that this will happen not only in China but more or less in all places of manufacturing and in the supply chain regardless of country.
But since China is also know for its replica market of course the concern is much higher when products comes from there and especially when bought by privet persons directly from there and not by medical companies with better resources to validate the products they buy.

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[RedSnake]

That also raises the question, why are the Chinese using English characters for their own standards? Maybe it's common practice?

English is a world language and Hongkong was "British" as many Asian countries, China sell there products to many none EU and US countries and then it is easier to also have the standards in English.

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[dik]

and I think part of the problem was that they didn't suggest masks soon enough and the 'authorities' were concerned that they would cause a 'run on' masks, leaving first responders without them.
Tnen it became political.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[zeusfaber]

In a rational world, it depends on what hazard you're trying to mitigate.

If I want to avoid breathing in harmful particulate, I'll choose an appropriate level of protection, buy something to a standard I understand from somewhere I trust and look for CE or UKCA marking through an accreditation body I recognise.

If I want to minimise my chances of passing Covid onto anybody else, then I'm going to:

a. Go nowhere near the rest of the population if I have any reason to suspect I'm infectious

b. Avoid poorly ventilated public spaces and ventilate the ones I have control over, so that virus concentrations are diluted sufficiently in the far field

c. Stay far enough away from other people (and encourage other people to do the same) to ensure people stay in that diluted far-field.

d. Wear some sort of covering over mouth and nose (and encourage others to do the same) to suppress the plume from coughs, sneezes and sighs of frustration, making the near field/far field boundary more predictable.

e. Trust other people to protect me in the same way, and give those who visibly don't deserve that trust an extremely wide berth.

Within that suite of protections, it doesn't make a right lot of difference whether the face covering is a GSR, something that complies with your favoured EN 149 or NIOSH standard, a Soviet Lepestok mask or a Chinese rip-off of a Gucci bandana.

A.

 

[Eufalconimorph]

I agree with Zeusfaber. I took to wearing a P100 respirator, with the exhalation valve covered in a surgical mask. Just as safe for everyone else as surgical masks (better than cloth), both safer and more comfortable for me. Edit: and it has the side benefit that I never have to smell cigarette smoke or other noxious smells when out around people.

 

[TugboatEng]

Not many know about the R and P series masks. If we truely believe masks work it's truely troublesome we didn't inform those that needed to know that oily environments significantly reduce the effectiveness of the N rated masks. Coincidentally, food prep workers got hit by COVID the hardest and they work on an oily environment. They should have never been allowed to wear N rates masks

Dik's last sentence alludes to that problem.

 

[IRstuff]

This looks to be a snipe hunt; it's pretty clear that the CDC is concerned about counterfeit KN95 masks; given that N95 masks are in abundance, why take the risk with masks that might have a 60% probability of being fake?

https://www.newsnationnow.com/health/coronavirus/how-can-you-tell-if-your-n95-or-kn95-mask-is-fake/

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

faq731-376 forum1529 Entire Forum list

http://www.eng-tips.com/forumlist.cfm

 

[spsalso]

Some time before Covid, my wife and I discovered that N95 masks did a pretty good job of filtering out the obnoxious smell of perfumes worn by people in public venues.

Perhaps I should spray myself with WD-40 and announce that it is MY choice of perfume.



spsalso

 

[TugboatEng]

N-95 doesn't filter odor. I buy the 3M 6001 series cartridges for my painters. They're N-95 for particles but also filter odors. I also give these cartridges to our crews when it's time to clean out the sewage digesters.

 

[CWB1]

I think part of the problem was that they didn't suggest masks soon enough and the 'authorities' were concerned that they would cause a 'run on' masks, leaving first responders without them.

I suspect a large portion of govt simply realized that they had a runaway media faux-fire, knew any action would have little impact, and were afraid of liability bc of it. Personally I'm thankful that we were back in work/school/etc before masks became a popular media discussion point bc it saved a ton of grief and money. I'm also all for PPE and supporting the elderly/unwell, but given the tiny-yet-noticeable numbers of young/healthy folks wearing masks today I feel its time for govt to publicly call-out the paranoia and push those folks toward seeking mental healthcare.

As for mask standards otherwise, the wife and I generally prefer fitted respirators to dust masks and make a habit of reading/following both SDS and 3M/other manufacturer's cartridge recommendations so the details are rather inconsequential.

 

[FacEngrPE]

OSHA does not assign a protection factor unless mask fit test is performed. If you really want masks to be protective the annual fit test is essential.

 

[spsalso]

N95 DOES filter odors, since we noticed the lack of them after donning same.

They do not filter ALL odors, I notice. Again, experimental results.

From this, I reason that they filter some odors, but not all.


spsalso

 

[drwebb]

May reduce the perception and/or penetration of odors, thereby being an effective countermeasure. But N95 masks are not designed to be adsorptive, and the size of typical fragrance molecules argue against a mechanical blocking (i.e. filtering) mechanism of action.

 

[FacEngrPE]

The fluff used to make N95 filters has a large surface area. It is possible that the large surface will attract some odor molecules (surface Adsorption), but the capacity is going to be quite limited.

 

[TugboatEng]

A real N-95 mask filters by electrostatic charge so there may be more capacity to catch aerosols than we would initially assume. I don't know the answer.

 

[RedSnake]

Maybe this perception about things smelling less or odors disappearing when using these masks isn't because of the mask itself but a consequence of it.
Mainly that even though you can breath through it, there is a slight pressure rice on the inside and maybe people unintentionally starts breathing more through there mouth and less through there nose when wearing them, so more of the outgoing air from the mouth goes to the nose meaning less molecules that is detected as smell can get in through the mask from the outside and into the nose.
So less smell.

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[Roga50]

About 20 years ago, I was a hospital IT employee (Florida). Being we all worked in patient care areas, we all had the same safety training as the medical staff. This included PPE rules. (quite a few times, I had to work on equipment in the operating rooms, for instance, where we had to suit up just like the medical staff).

We had a rule that NOBODY was permitted to use an N95 mask unless we were properly fitted for it (the procedure included being put in a hood with some sort of super sweet smelling aerosol added, to confirm that we could not smell it).

When I saw people using N95's, of course this concerned me, as they had a false sense of security.

 

[TugboatEng]

In terms of permissible exposure limits, an ill firing respirator must be better than no respirator at all. However, it's difficult to determine whether one's exposure is permissible without control of the fit.

With that said, there is no PEL for viruses. Theoretically, infection can start with a single virus exposure.

 

[RedSnake]

Theoretically, infection can start with a single virus exposure.

Hmmm maybe if you are totally out of a immune system.
Otherwise one single virus would just boost your immune system, put it in the memory bank and wait for the next attack, better prepared.

“Logic will get you from A to Z; imagination will get you everywhere.“
Albert Einstein

 

[TugboatEng]

The chances of a virus making it to a cell it can infect are small but once there, in the case of today's most relevant virus, 10^5 copies are produced from the first cell. Individually, I think those copies will have a much higher chance of being infectious because they are released directly in the vicinity of the first infectable cell and similar cells tend to be grouped together. The spread from a single infection may be considerably more than exponential.

I think this possibility is the reason there are no acceptable exposure limits to any pathogenic substances.